The focus of this laboratory has been the MHC class I molecule, classically considered a molecular heterodimer consisting of a 46 kd polymorphic heavy chain, exemplified by the murine H-2K, D, and L molecules (analogous to the human HLA-A, -B, and -C molecules), that is non-covalently assembled with the 12 kd monomorphic light chain, beta2-microglobulin. Our objectives in this project have been to examine the interaction of self and antigenic peptides to the MHC class I molecule using several different systems and to evaluate these interactions in three dimensional computer modeling studies based on crystallographic MHC structures.